2017-12-06 14:19:05

by Arnd Bergmann

[permalink] [raw]
Subject: [PATCH] btrfs: tree-checker: use %zu format string for size_t

The return value of sizeof() is of type size_t, so we must print it
using the %z format modifier rather than %l to avoid this warning
on some architectures:

fs/btrfs/tree-checker.c: In function 'check_dir_item':
fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]

Fixes: 005887f2e3e0 ("btrfs: tree-checker: Add checker for dir item")
Signed-off-by: Arnd Bergmann <[email protected]>
---
fs/btrfs/tree-checker.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
index 66dac0a4b01f..7c55e3ba5a6c 100644
--- a/fs/btrfs/tree-checker.c
+++ b/fs/btrfs/tree-checker.c
@@ -270,7 +270,7 @@ static int check_dir_item(struct btrfs_root *root,
/* header itself should not cross item boundary */
if (cur + sizeof(*di) > item_size) {
dir_item_err(root, leaf, slot,
- "dir item header crosses item boundary, have %lu boundary %u",
+ "dir item header crosses item boundary, have %zu boundary %u",
cur + sizeof(*di), item_size);
return -EUCLEAN;
}
--
2.9.0


2017-12-06 14:25:05

by David Sterba

[permalink] [raw]
Subject: Re: [PATCH] btrfs: tree-checker: use %zu format string for size_t

On Wed, Dec 06, 2017 at 03:18:14PM +0100, Arnd Bergmann wrote:
> The return value of sizeof() is of type size_t, so we must print it
> using the %z format modifier rather than %l to avoid this warning
> on some architectures:
>
> fs/btrfs/tree-checker.c: In function 'check_dir_item':
> fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]
>
> Fixes: 005887f2e3e0 ("btrfs: tree-checker: Add checker for dir item")
> Signed-off-by: Arnd Bergmann <[email protected]>

Reviewed-by: David Sterba <[email protected]>

2017-12-07 00:32:57

by Qu Wenruo

[permalink] [raw]
Subject: Re: [PATCH] btrfs: tree-checker: use %zu format string for size_t



On 2017年12月06日 22:18, Arnd Bergmann wrote:
> The return value of sizeof() is of type size_t, so we must print it
> using the %z format modifier rather than %l to avoid this warning
> on some architectures:
>
> fs/btrfs/tree-checker.c: In function 'check_dir_item':
> fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]

Any idea about which architecture will cause such warning?
On x86_64 I always fail to get such warning.

>
> Fixes: 005887f2e3e0 ("btrfs: tree-checker: Add checker for dir item")

Reviewed-by: Qu Wenruo <[email protected]>

Thanks,
Qu

> Signed-off-by: Arnd Bergmann <[email protected]>
> ---
> fs/btrfs/tree-checker.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c
> index 66dac0a4b01f..7c55e3ba5a6c 100644
> --- a/fs/btrfs/tree-checker.c
> +++ b/fs/btrfs/tree-checker.c
> @@ -270,7 +270,7 @@ static int check_dir_item(struct btrfs_root *root,
> /* header itself should not cross item boundary */
> if (cur + sizeof(*di) > item_size) {
> dir_item_err(root, leaf, slot,
> - "dir item header crosses item boundary, have %lu boundary %u",
> + "dir item header crosses item boundary, have %zu boundary %u",
> cur + sizeof(*di), item_size);
> return -EUCLEAN;
> }
>


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2017-12-07 09:06:54

by Arnd Bergmann

[permalink] [raw]
Subject: Re: [PATCH] btrfs: tree-checker: use %zu format string for size_t

On Thu, Dec 7, 2017 at 1:32 AM, Qu Wenruo <[email protected]> wrote:
>
>
> On 2017年12月06日 22:18, Arnd Bergmann wrote:
>> The return value of sizeof() is of type size_t, so we must print it
>> using the %z format modifier rather than %l to avoid this warning
>> on some architectures:
>>
>> fs/btrfs/tree-checker.c: In function 'check_dir_item':
>> fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]
>
> Any idea about which architecture will cause such warning?
> On x86_64 I always fail to get such warning.

I think all 32-bit architectures:

#ifndef __kernel_size_t
#if __BITS_PER_LONG != 64
typedef unsigned int __kernel_size_t;
typedef int __kernel_ssize_t;
typedef int __kernel_ptrdiff_t;
#else
typedef __kernel_ulong_t __kernel_size_t;
typedef __kernel_long_t __kernel_ssize_t;
typedef __kernel_long_t __kernel_ptrdiff_t;
#endif
#endif

Arnd

2017-12-07 15:10:40

by David Sterba

[permalink] [raw]
Subject: Re: [PATCH] btrfs: tree-checker: use %zu format string for size_t

On Thu, Dec 07, 2017 at 08:32:04AM +0800, Qu Wenruo wrote:
>
>
> On 2017年12月06日 22:18, Arnd Bergmann wrote:
> > The return value of sizeof() is of type size_t, so we must print it
> > using the %z format modifier rather than %l to avoid this warning
> > on some architectures:
> >
> > fs/btrfs/tree-checker.c: In function 'check_dir_item':
> > fs/btrfs/tree-checker.c:273:50: error: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'u32' {aka 'unsigned int'} [-Werror=format=]
>
> Any idea about which architecture will cause such warning?
> On x86_64 I always fail to get such warning.

The intel 0-day build bot compiles on various architectures and 32/64
setups, I'm not sure if this warning has been reported, no such mail in
my mboxes.